• 제목/요약/키워드: Air-conditioner

검색결과 777건 처리시간 0.03초

건설 안전관리자의 특성 및 프로젝트 특성이 에어컨 설치 공사의 안전 점수에 미치는 영향 (Impact of Construction Safety Managers and Project Characteristics on Air Conditioning Installation Safety Scores)

  • 엄미영;김진영;김홍조
    • 한국건축시공학회지
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    • 제24권3호
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    • pp.381-391
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    • 2024
  • 안전관리자는 체크리스트를 기반으로 자신의 경험, 지식, 및 프로젝트의 특성을 종합하여 작업 환경의 위험을 평가한다. 이러한 방법은 안전관리자 간의 위험 인식의 차이를 가져올 수 있다. 에어컨 시공 분야에서의 산업재해가 증가하고 있음에도 불구하고, 대부분의 연구가 대규모 프로젝트에 집중되어 있어, 에어컨 시공 분야의 특수한 안전관리 요구 사항을 충족시키는 체크리스트 개발에 한계가 있다. 이에 본 연구는 에어컨 설치 공사에 종사하는 안전관리자들의 개인적 특성(연령, 전공)과 공사 관련 요소(공사 비용, 착수 시기)가 체크리스트에 따른 안전 점수에 미치는 영향을 분석하고자 한다. A사로부터 수집한 7,046건의 안전 점수 데이터의 분석 결과, 프로젝트의 착수 시기가 안전 점수에 가장 큰 영향을 미쳤으며(0.21), 안전관리자의 연령 역시 제한적으로 영향을 미치는 것으로 나타났다(0.06). 그러나, 안전관리자의 전공은 점수에 영향을 주지 않았으며, 프로젝트의 공사 비용은 안전 점수와 음의 관계(-0.1)를 보였다. 이 연구는 프로젝트의 규모와 시기를 고려한 맞춤형 안전 작업 체크리스트 개발의 필요성과 다양한 연령의 안전관리자를 균형있게 배치하는 전략의 중요성을 강조한다.

토양개량제 시용이 토양물리성과 담배생육에 미치는 영향 (Effect of Some Soil Conditioners on Soil Physical Properties and Tobacco Growth)

  • 이철환;진정의;한철수
    • 한국작물학회지
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    • 제41권6호
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    • pp.685-691
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    • 1996
  • 답전전환지의 잎담배 품질을 밭담배 수준으로 향상시키기 위한 재배법 개선의 기초자료로 이용 하고자 몇가지 토양개량제를 처리하여 토양의 입단형성량과 안정성등의 물리성 개선효과를 분석하고 잎담배 생육에 미친 영향을 조사한 결과는 다음과 같다. 1. 토양의 내수성 입단형성량은 polyvinylalco-hol(PVA) > perlite > zeolite순으로 많았고 식생에 적당한 크기(0.25~l.0mm)의 입단형성률은 PVA처리구에서 가장 높았다. 2. 내수성 입단형성률은 토양수분 함량이 높을 수록 입단화률도 증가하여 50%구에서 가장 높았으나 형성된 입원은 직경 2mm이상의 큰 입단비률이 높아 식생에 적당한 크기(0.25~l.00mm)의 입단형성량과 실제 농기계의 작업능률등을 고려하면 토양수분은 40%구가 적당할 것으로 판단되었다. 3. 토양립단의 안정성, 통기성 및 투수성은 토양개양제 처리로 무처리에 비해 현저히 증가되고 PVA처리구가 가장 양흐하였으며, 공린률도 무처리에 비해 다소 증가되는 경향이나 개량제종류간에는 대등하게 나타났다. 4. 토양개량제 처리로 토양 3상 비율의 개선효과가 인정되었고, 통기성은 zeolite perlite처리구가, 투수성은 PVA처리구가 높았으며, 무처리구에 비해 전체적으로 보수력이 증대되었다. 5. 연초의 생육량은 전 수량 구성요소에서 개량제처리로 현저히 증가하였고 지상부에 비해 지하부의 생장량 증가가 더 크게 나타났으며, 생장양과 연계한 토양개량제의 물리성 개선효과는 PVA > perlite > zeolite순으로 나타났다.

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설비공학 분야의 최근 연구 동향: 2014년 학회지 논문에 대한 종합적 고찰 (Recent Progress in Air-Conditioning and Refrigeration Research: A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2014)

  • 이대영;김사량;김현정;김동선;박준석;임병찬
    • 설비공학논문집
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    • 제27권7호
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    • pp.380-394
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    • 2015
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2014. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of heat and mass transfer, cooling and heating, and air-conditioning, the flow inside building rooms, and smoke control on fire. Research issues dealing with duct and pipe were reduced, but flows inside building rooms, and smoke controls were newly added in thermal and fluid engineering research area. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results for thermal contact resistance measurement of metal interface, a fan coil with an oval-type heat exchanger, fouling characteristics of plate heat exchangers, effect of rib pitch in a two wall divergent channel, semi-empirical analysis in vertical mesoscale tubes, an integrated drying machine, microscale surface wrinkles, brazed plate heat exchangers, numerical analysis in printed circuit heat exchanger. In the area of pool boiling and condensing, non-uniform air flow, PCM applied thermal storage wall system, a new wavy cylindrical shape capsule, and HFC32/HFC152a mixtures on enhanced tubes, were actively studied. In the area of industrial heat exchangers, researches on solar water storage tank, effective design on the inserting part of refrigerator door gasket, impact of different boundary conditions in generating g-function, various construction of SCW type ground heat exchanger and a heat pump for closed cooling water heat recovery were performed. (3) In the field of refrigeration, various studies were carried out in the categories of refrigeration cycle, alternative refrigeration and modelling and controls including energy recoveries from industrial boilers and vehicles, improvement of dehumidification systems, novel defrost systems, fault diagnosis and optimum controls for heat pump systems. It is particularly notable that a substantial number of studies were dedicated for the development of air-conditioning and power recovery systems for electric vehicles in this year. (4) In building mechanical system research fields, seventeen studies were reported for achieving effective design of the mechanical systems, and also for maximizing the energy efficiency of buildings. The topics of the studies included energy performance, HVAC system, ventilation, and renewable energies, piping in the buildings. Proposed designs, performance performance tests using numerical methods and experiments provide useful information and key data which can improve the energy efficiency of the buildings. (5) The field of architectural environment was mostly focused on indoor environment and building energy. The main researches of indoor environment were related to the evaluation of work noise in tunnel construction and the simulation and development of a light-shelf system. The subjects of building energy were worked on the energy saving of office building applied with window blind and phase change material(PCM), a method of existing building energy simulation using energy audit data, the estimation of thermal consumption unit of apartment building and its case studies, dynamic window performance, a writing method of energy consumption report and energy estimation of apartment building using district heating system. The remained studies were related to the improvement of architectural engineering education system for plant engineering industry, estimating cooling and heating degree days for variable base temperature, a prediction method of underground temperature, the comfort control algorithm of car air conditioner, the smoke control performance evaluation of high-rise building, evaluation of thermal energy systems of bio safety laboratory and a development of measuring device of solar heat gain coefficient of fenestration system.

고온기 분만사 내 냉방 시설의 종류가 모돈의 번식성적 및 스트레스 지표에 미치는 영향 (Effect of Different Cooling System on Performance and Hair Cortisol on Sows under Heat Stress)

  • 오승민;최요한;김동우;하상훈;김조은;정현정;김진수
    • 한국산학기술학회논문지
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    • 제22권3호
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    • pp.160-168
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    • 2021
  • 본 연구는 고온기 분만사 내 냉방 시설의 종류가 모돈의 번식성적 및 스트레스 지표에 미치는 영향을 구명하기 위하여 실시되었다. 본 실험을 위해 경산돈(Landrace×Yorkshire; 242.84±2.89 kg) 40두를 공시하였으며, 냉방 시설에 기반하여 4처리 10반복, 반복당 1두씩 완전임의 배치하였다. 실험 처리구는 쿨링패드(CP; Cooling pad), 에어컨(AC, Air conditioner), 스나웃 쿨링(SC, Snout cooling) 및 안개분무(MS, Mist spray)로 구성되었으며, 포유기간(21일) 동안 진행되었다. 모돈의 성적에서 일일사료섭취량은 포유기간에서 CP 및 AC 처리구가 유의적으로 높게 나타났다(p<0.05). 이유 시, 자돈의 체중은 AC처리구가 유의적으로 가장 높게 나타났으며(p<0.05), SC처리구가 유의적으로 가장 낮게 나타났다(p<0.05). 모돈의 코티졸 농도는 SC 및 MS처리구가 CP 및 AC처리구보다 유의적으로 높게 나타났다(p<0.05). 자돈의 코티졸 농도는 MS처리구가 유의적으로 가장 높게 나타났으며(p<0.05), CP처리구가 유의적으로 가장 낮게 나타났다(p<0.05). 모돈의 호흡수 및 직장온도는 MS처리구가 유의적으로 가장 높게 나타났으며(p<0.05), AC처리구가 유의적으로 가장 낮게 나타났다(p<0.05). 결론적으로, 쿨링패드 및 에어컨 냉방시설이 스나웃 쿨링 및 안개분무 냉방시설보다 모돈의 생산성을 개선시킬 수 있을 것으로 사료된다.

대형강의실의 환기여부에 따른 실내환경과 피로감 반응의 차이분석 (Analysis of Differences in Indoor Environment and Fatigue Response According to Ventilation in Lecture Hall)

  • 오예슬;황진아;최윤정
    • 한국생활과학회지
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    • 제19권2호
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    • pp.417-428
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    • 2010
  • The purpose of this study was to analyze differences of the indoor environment and student's fatigue response according to ventilation in university lecture hall. The experiments consisted of measuring the indoor environmental parameters and a survey of student's responses. The experiments were in the lecture hall that the actual lecture was conducted in on the $25^{th}$ of May 2009 (not opening windows and door- A) and the $1^{st}$ of June 2009 (opening windows and door- B). The experimental variable was ventilation by opening the windows and door, and the controlled conditions were indoor temperature by air conditioner, volume of the microphone and VTR, lighting conditions and teaching method. The results are as follows: 1) The indoor temperature was maintained in controlling A, B but the $CO_2$ and relative humidity of A (average 3579ppm, 62.6%) was higher than B (average 1697ppm, 48.1%). 2) There were differences in the student's subjective responses and student's fatigue responses between A and B. 3) Therefore, it was found that ventilation by opening the windows and door was a valid way to improve the relative humidity and to reduce $CO_2$ in the lecture hall.

열펌프의 고장감지 및 진단시스템 구축을 위한 실시간 정상상태 진단기법 개발 (Technology for Real-Time Identification of Steady State of Heat-Pump System to Develop Fault Detection and Diagnosis System)

  • 김민성;윤석호;김민수
    • 대한기계학회논문집B
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    • 제34권4호
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    • pp.333-339
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    • 2010
  • 고장감지 및 진단(FDD) 시스템의 구축의 기초 연구로 정상상태 진단기에 대한 연구를 수행하였다. 정상상태에 대한 진단은 시스템 전체를 관찰하거나 몇몇 필요한 시스템 파라미터를 모니터링 함으로써 가능하다. 최적화된 정상상태 진단기를 이용하면 FDD 시스템에서 필수적인 정상운전 시의 기준모델(no fault reference model)을 자가학습을 통하여 적용할 수 있다. 본 연구에서는 가정용 열펌프가 냉방조건으로 작동할 경우에 대해 이동창을 기반으로 7개의 측정값들에 대한 표준편차를 분석함으로써 정상상태 판정을 내리도록 하였다. 정상상태 진단기의 작동의 여부는 실내부하를 조절함으로써 확인하였다. 본 연구를 통하여 열펌프 등의 증기압축 사이클 시스템에 대하여 이동창을 기반으로 한 정상상태 진단기 개발 방법을 제시하였다.

일부 생활화학용품에 함유된 성분 및 유해물질 조사 - 세정제와 소독제를 중심으로 - (An Investigation of Ingredients and Hazardous Substances in Some Consumer Products - Focusing on Cleaners and Disinfectants -)

  • 허다안;허은혜;박지영;문경환;이기영
    • 한국환경보건학회지
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    • 제41권5호
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    • pp.314-326
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    • 2015
  • Objectives: This study was conducted to identify the ingredients used in ten consumer product categories and determine hazardous substances among these ingredients. Methods: A total of 542 commercial products in ten consumer product categories were selected. The consumer products were sticker removers, washing machine cleaners, multi-purpose cleaners, mold removers, glass cleaners, chlorinated sanitizers, air conditioner cleaners, disposal cleaners, drain cleaners and disinfectant sprays. The company list was complied from governmental records and a market survey. The respective companies were contacted for a list of ingredients found in the 542 products. Results: The corresponding companies listed 163 ingredients. According to European Union (EU) Directive 67/548/EEC, 38 of the 163 ingredients were classified as dangerous substances. Among these substances, 28 ingredients were hazardous to the skin, 15 were hazardous to the eye, and nine were hazardous if inhaled. Three ingredients were classified as CMR (carcinogenic, mutagenic or toxic for reproduction) substances: liquefied petroleum gases (LPG) with carcinogenicity and mutagenicity, and VM&P naphtha and ligroine with carcinogenicity. Conclusion: Various chemicals, including hazardous substances, were used in consumer products. Risk assessment of consumer products is required in order to protect the population from health risks.

Predicted Mean Vote(PMV)를 이용한 겨울철 종합병원의 실내 온·열 환경의 평가 (Assessment of Thermal Comfort in a General Hospital in Winter Using Predicted Mean Vote (PMV))

  • 이보람;김정훈;김규상;김혜진;이기영
    • 한국환경보건학회지
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    • 제41권6호
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    • pp.389-396
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    • 2015
  • Objectives: A hospital is a complex building that serves many different purposes. It has a major impact on patient's well-being as well as on the work efficiency of the hospital staff. Thermal comfort is one of the major factors in indoor comfort. The purpose of this study was to determine thermal comfort in various locations in a hospital. Methods: Various indoor environmental conditions in a general hospital were measured in February 2014. The predicted mean vote (PMV) and carbon dioxide ($CO_2$) concentration were measured simultaneously in the lobby, office, restaurant, and ward. Results: The ward was the most thermally comfortable location (PMV=0.44) and the lobby was the most uncomfortable (PMV = -1.39). However, the $CO_2$ concentration was the highest in the ward (896 ppm) and the lowest in the lobby (572 ppm). The average PMV value was the most comfortable in the ward and the lowest in the lobby. In contrast, for concentration of carbon dioxide, the highest average was in the ward and the lowest in the lobby. Due to air conditioner operation, during operating hours the PMV showed values close to 0 compared to the non-operating time. Correlation between PMV and $CO_2$ differed by location. Conclusion: The PMV and concentration of carbon dioxide of the hospital lobby, office, restaurant and ward varied. The relationship between PMV and carbon dioxide differed by location. Consideration of how to apply PMV and carbon dioxide is needed when evaluating indoor comfort.

중학생의 주거 환경과 사회적 성숙도와의 관계 연구 (A Study on Relationships Between Residential Environments and the Social Maturity of Middle School Students)

  • 김세희;곽경숙
    • 한국생활과학회지
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    • 제19권1호
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    • pp.215-225
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    • 2010
  • This study had the purpose of presenting a residential environment solution as a desirable educational environment for middle school students to grow soundly and to achieve proper self-realization while providing basic materials to build up a suitable residential environment by comparing and analyzing what relationships exist between different home backgrounds, residential environments and middle school students' social maturity. This research was conducted from Feb. 11, 2008 to Feb. 13, 2008. The subject of this research was 601 students in 3 middle schools located in Gyunggi-do. The data analyzed used the SPSS 11.5 version. The summary of this study's results is as follows. First, in terms of home background, the higher the parents' educational background and social and economic position, the greater the students' social maturity. Second, in terms of home environment, the more spacious the living space, the better the water and sewage system and rest room, the more convenient the air conditioner and kitchen system, the better the lighting, ventilation, soundproofness, insulation, the less the danger in relation to fire, crime, traffic accidents, disaster, the greater the students' social maturity. Third, in terms of the home environment related to the correlation between the residential environment and social maturity, all areas such as housing facilities, housing structural environment and housing safety showed static correlations and proved that the residential environment has an important influence on social maturity. Accordingly, in order to build up an ideal residential environment, we should make efforts to expand and improve better facilities at home considering privacy, lighting, ventilation, soundproofness, heating etc. and remove unsound factors that obstruct students social maturity and build up clean and safe residential environment with good relations with their neighbors.

공동주택에서 지열 냉난방 시스템 적용시 경제성 분석 (Economic Analsys of Cooling-Heating System Using Ground Source Heat in Multi Family Apartment)

  • 박용부;박종배;임해식;백성권
    • 한국지반환경공학회 논문집
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    • 제8권3호
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    • pp.11-18
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    • 2007
  • 본 연구에서는 파급효과가 큰 공동주택에서 지열 냉난방 시스템의 경제성을 아파트 분양평형, 운전시간, 냉난방 및 급탕 설치형태별로 구분하여 초기 공사비 증가, 운전비 절감액, 초기 투자비 회수기간등을 산정하였다. 냉난방 및 급탕 운전시간이 많을수록 초기 공사비 증가액에 비해 운전비용 절감액이 커 초기 투자비 회수기간이 단축되었다. 전용면적이 클수록 투자회수 기간이 길었으며 냉난방 및 급탕 설치형태에서는 냉난방을 지열원, 급탕을 폐열회수한 경우가 초기 투자 회수기간이 가장 짧았다. 기존 시스템(패키지 에어콘, LNG 난방 및 급탕)에 비해 냉난방, 급탕을 모두 지열로 이용하는 경우, 냉난방은 지열, 급탕은 폐열을 이용하는 경우, 냉난방은 지열, 급탕은 LNG인 경우에 공사비가 $m^2$당 각각 약 72,000원, 66,900원, 62,300원 정도 증가하였다.

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